Project Summary/Abstract Chronic pain and opioid overdose are two critical public health problems in the US. About 25 million adults (11%) suffer from chronic daily pain and up to 8 million use opioids to manage chronic pain. Unfortunately, 46 people die daily from overdose of prescription opioids. For safe chronic opioid therapy for chronic pain, physicians monitor patients? adherence to prescription opioids, and reduce or discontinue the prescription as indicated. Yet, adherence and cessation are not easy for some patients and one reason is opioid craving, a strong desire or urge to use opioids. Our preliminary data show about 32% of patients on chronic opioid therapy report craving. Craving is strongly associated with opioid misuse and negative health outcomes. To date, we do not fully understand the underlying mechanisms of prescription opioid craving in chronic pain sufferers, and psychological treatment targets to reduce craving. Based on our pilot survey, patients endorsing craving reported greater pain catastrophizing than those endorsing no craving. Our other survey study also reported a positive link between pain catastrophizing and opioid craving in patients on chronic opioid therapy for chronic pain conditions. Although these findings propose a possibility that lowering pain catastrophizing may decrease opioid craving, cross- sectional observational studies are limited in investigating a causal association. Potentially, pain catastrophizing enhances stress-induced opioid craving because stress-induced opioid craving is a well-established phenomenon in studies of addiction, and pain catastrophizing is associated with greater pain and emotional distress in patients with chronic pain. Therefore, the proposed project seeks to determine: a) the effect of pain catastrophizing on prescription opioid craving in patients on chronic opioid therapy for chronic pain and b) psychological (negative affect) and physiological (cortisol, norepinephrine) distress as potential mediating variables. The proposed study will use the previously validated protocol to temporarily induce and reduce pain catastrophizing and assess changes in opioid craving, negative affect, and stress hormones before and after pain catastrophizing manipulation. Additionally, this proposed study prospectively administers the protocol to reduce pain catastrophizing by thinking about and rehearsing a coping statement daily for 7 days and monitor daily opioid craving, opioid use and misuse, and negative affect for 14 days. The current project is expected to characterize the role of pain catastrophizing in opioid craving and opioid misuse, and pain catastrophizing as a critical psychological treatment target for reducing prescription opioid craving and improving prescription adherence. Furthermore, the protocol to manipulate pain catastrophizing can facilitate future research to study causal mechanisms involved in pain catastrophizing and the protocol to rapidly stabilize pain catastrophizing can be used clinically to improve the health outcome of patients taking prescription opioid for chronic pain.